SummaryThe study of fluctuations in athletic performance attributable to the menstrual cycle has been an area of considerable interest and controversy for well over half a century. Studies have included simple observations of performance in athletic events, and have also documented specific physical psychological and physiological changes as they relate to varying hormonal levels of the menstrual cycle.Advantages and disadvantages to human performance have been attributed to various phases of the cycle. Many investigators have documented evidence to suggest that the premenstrual phase is often associated with decreased performance. Others have noted that there are specific physiological changes, inherent in athletic performance, occurring in the follicular and luteal phases of the menstrual cycle. However, it is evident that there is conflict within the literature.This review considers the evidence for the cyclic effects of the regular or normal menstrual cycle on performance. It examines surveyed evidence of the effects of the regular menstrual cycle on athletic performance, effects on psychological and perceptual factors, maximum oxygen uptake, endurance and time to fatigue, temperature, sweating, body-weight, respiratory drive, blood lactate, carbohydrate and lipid metabolism, and cardiovascular parameters.It is concluded that there is considerable variation in the findings of the literature and that any reported variations in performance may well be greatly influenced by intersubject variability, the nature of the exercise, and the nutritional status of the athlete, as well as minor changes that could be attributable to the menstrual cycle.